Server Device, Control Method Performed by the Server Device, Program, and Terminal Device

ABSTRACT

An item can be provided to a user by a lottery and the item odds can be changed in accordance with a prescribed condition. A control method, performed by a server device connected via a communication line to a terminal device operated by a user, comprises the step of selecting a lottery mode from among a plurality of lottery modes, the step of following the selection of the lottery mode, holding a drawing from among a plurality of types of items on the basis of the selected lottery mode, and the step of following the holding of the drawing, providing the won item to the terminal device.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the priority of Japanese Patent Application No.2013-070196, filed Mar. 28, 2013, which is incorporated herein byreference in its entirety.

BACKGROUND

Disclosed herein are a server device, a control method performed by theserver device, a program, and a terminal device.

Conventionally, there are many techniques related to a server devicewhich provides a game in which a user plays a match-type battle orcompletes a quest using the items he/she owns. For example,JP2008-220984A discloses a game server which comprises: image datastoring means which stores image data for displaying game images,message data storing means which stores message data for displayingmessages including rules, and control means which outputs a rulemessage, before a game starts, in a manner perceivable by a game player,displays on a display device a game image corresponding to the rulemessage on the basis of the image data and, after the game starts,displays on the display device a game image related to the game on thebasis of the image data.

SUMMARY

With conventional techniques as in the game server of JP2008-220984A,the ways of acquiring battle cards are limited, leading to degradationof the user's interest in the game. As it is particularly difficult toacquire highly rare items, the user may have an impression that there isno chance of acquiring such an item, in which case the user's interestin the game will decrease considerably.

In view of the foregoing, an object of various embodiments of thepresent invention is to provide a server device which enables an item tobe provided by a lottery and allows the item odds to be changed inaccordance with a prescribed condition, and also to provide a controlmethod performed by the server device, a program, and a terminal device.

A method according to the invention comprises a control method performedby a server device which is connected via a communication line to aterminal device operated by a user. The control method may comprise: thestep of selecting a lottery mode from among a plurality of lotterymodes; the step of, following the selection of the lottery mode, holdinga drawing from among a plurality of types of items on the basis of theselected lottery mode; and the step of, following the holding of thedrawing, providing the won item to the terminal device.

In the above-described lottery mode, the odds of winning a prescribedtype of item among the plurality of types of items may be increased.

The control method may further include the step of storing the itemacquired by the user, wherein in the lottery mode, the odds of winningan item that the user has not acquired yet among the plurality of typesof items may be increased.

The above-described step of selecting a lottery mode may include a stepof holding a lottery to select a lottery mode from among the pluralityof lottery modes.

The control method may further include the step of storing userinformation associating the user with at least one of level, gameprogress, acquired items, and playing time, wherein in the step ofholding a lottery to select a lottery mode, the lottery mode selected inthe lottery may be varied in accordance with the user information.

A server device according to the invention comprises a server devicewhich is connected via a communication line to a terminal deviceoperated by a user. The server device may include: a lottery modeselecting unit which selects a lottery mode from among a plurality oflottery modes; a lottery unit which is operable, in response to theselection of the lottery mode, to hold a drawing from among a pluralityof types of items on the basis of the selected lottery mode; and aproviding unit which is operable, in response to the holding of thedrawing, to provide the won item to the terminal device.

A terminal device according to the invention comprises a terminal devicewhich is operated by a user and connectable to a server device via acommunication line. The terminal device includes a processor which mayperform the steps of: receiving, from the server device, a lottery modeselected from among a plurality of lottery modes; displaying thereceived lottery mode on a display; displaying a presentation of holdinga drawing from among a plurality of types of items on the basis of thereceived lottery mode; and displaying the item won in the drawing on thedisplay.

A system according to the invention comprises a system which includes aterminal device operated by a user and a server device connected to theterminal device via a communication line. The system may include: alottery mode selecting unit which selects a lottery mode from among aplurality of lottery modes; a lottery unit which is operable, inresponse to the selection of the lottery mode, to hold a drawing fromamong a plurality of types of items on the basis of the selected lotterymode; and a providing unit which is operable, in response to the holdingof the drawing, to provide the won item to the terminal device.

A server device according to the invention comprises a server devicewhich is connected via a communication line to a terminal deviceoperated by a user. The server device may include: means for selecting alottery mode from among a plurality of lottery modes; means operable, inresponse to the selection of the lottery mode, for holding a drawingfrom among a plurality of types of items on the basis of the selectedlottery mode; and means operable, in response to the holding of thedrawing, for providing the won item to the terminal device.

A storage medium according to the invention comprises acomputer-readable storage medium having recorded therein a process forcausing a computer to perform steps which may include: the step ofgetting connected via a communication line to a terminal device operatedby a user; the step of selecting a lottery mode from among a pluralityof lottery modes; the step of, following the selection of the lotterymode, holding a drawing from among a plurality of types of items on thebasis of the selected lottery mode; and the step of, following theholding of the drawing, providing the won item to the terminal device.

The program of the invention may be installed or loaded to a computer bydownloading it from a recording medium, such as an optical disk like aCD-ROM, a magnetic disk, or a semiconductor memory, or downloading itthrough a communication network.

In the specification, the “unit” does not solely mean a physicalstructure. It also includes the case where a function of the structureis implemented by software. Further, a function of a structure may beimplemented by two or more physical structures, or functions of two ormore structures may be implemented by a single physical structure.

With the control method according to the invention, which is performedby a server device connected via a communication line to a terminaldevice operated by a user and which includes the step of selecting alottery mode from among a plurality of lottery modes, the step offollowing the selection of the lottery mode, holding a drawing fromamong a plurality of types of items on the basis of the selected lotterymode, and the step of following the holding of the drawing, providingthe won item to the terminal device, it becomes possible to provide anitem by a lottery and change the item odds in accordance with aprescribed condition.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a configuration diagram of a game system including a serverdevice according to a first embodiment;

FIG. 2 is a block diagram of the server device in the first embodiment;

FIG. 3 shows an item information table in the first embodiment;

FIG. 4 shows a user information table in the first embodiment;

FIG. 5 shows a mode information table in the first embodiment;

FIG. 6 shows an exemplary mode lottery screen in the first embodiment;

FIG. 7 is a chart illustrating the process flow of the server device inthe first embodiment;

FIG. 8 illustrates screen transitions in the first embodiment;

FIG. 9 is a chart illustrating the process flow of odds controlprocessing in the first embodiment; and

FIG. 10 is another chart illustrating the process flow of the oddscontrol processing in the first embodiment.

DETAILED DESCRIPTION

A first embodiment of the invention will be described below withreference to FIGS. 1 to 10.

FIG. 1 is a system configuration diagram of a game system 10 including aserver device 100 according to the embodiment. As shown in FIG. 1, theserver device 100 is a server computer connected to a network 300 suchas the Internet or a dedicated line. Besides the server device 100,terminal devices, i.e. mobile terminals 200A to 200D (hereinafter, themobile terminals 200A to 200D will be collectively referred to as“mobile terminal(s) 200”), are connected to the network 300 in a wiredor wireless manner. The server device 100 and the mobile terminals 200,which are made communicable with each other, constitute the game system10.

The game system 10 will be outlined first.

A user of this game system 10 uses a mobile terminal 200, connected tothe network 300, to get connected to the server device 100, to therebyreceive a game provided. The user who has been connected to the serverdevice 100 can draw lots to acquire, from the server device 100, itemsnecessary for the progress of the game.

The mobile terminal 200 is an information processing device having thefunction of communicating with the server device 100 via the network300. Specifically, the mobile terminal 200 may be a mobile phone, smartphone, notebook PC, PDA, or the like. Although not shown in FIG. 1, themobile terminal 200 preferably comprises a main control unit including aCPU and memory, a communication unit for connecting the terminal to thenetwork 300, an input unit such as a touch panel for accepting useroperations, and a display unit which displays an item lottery result.Although the terminal used by a user to access the server device 100 isthe mobile terminal 200 in the embodiment, not limited thereto, it maybe a desktop PC or other terminal device which is not portable, forexample.

There are a plurality of types of items the user can acquire using themobile terminal 200. They may include, for example: skill-improvingitems, which increase or improve attack power, defense power, or hitpoints of a player manipulated by the user when the player fights withan enemy character in the game; recovery items, which restore theplayer's hit points; attack items, which are used to attack an enemycharacter; and defense items, which are used to defend the playeragainst an attack from an enemy character. As used herein, the “skill”means the ability to do a specific action such as attack, defense,recovery, or special attack.

It is desirable that the attack and defense items each have, as aparameter, an attribute such as fire, water, or thunder indicatingchemistry with an enemy character. For example, it may be configuredsuch that an attack item having the water attribute can be used as aneffective attacking tool against the enemy character having the fireattribute. In addition to the attribute, other parameters such as attackpower, defense power, hit points, rarity, etc. may be set for each item.For example, the rarity is desirably ranked in accordance with therarity value of the item. The odds of winning each item in a lottery(hereinafter, referred to as “item odds”) vary among patterns (describedlater) which associate respective items with item odds. The state inwhich an item lottery is held in a prescribed pattern is called a“mode”.

The configuration of the server device 100 will now be described withreference to FIG. 2. FIG. 2 is a block diagram of the server device 100.As shown in FIG. 2, the server device 100 comprises a control unit 110,an input unit 120, a storage unit 130, and a communication unit 140.

The control unit 110 comprises an arithmetic processing unit 111 such asa CPU or MPU, an image processing unit 112, and a memory 113 such as aRAM. The arithmetic processing unit 111 executes a program recorded inthe storage unit 130, on the basis of inputs, to cause the functionalunits to operate. The program may be stored in a storage medium such asa CD-ROM, or distributed via the network 300, and installed into thecomputer. The memory 113 temporarily stores a server program, a gameprogram, and various kinds of data necessary for computation duringexecution of the processing in the programs.

The image processing unit 112 generates images to be transmitted to theuser mobile terminal 200. The images generated by the image processingunit 112 specifically include an image of an item, an image of an itemlottery screen, and an image of a mode lottery screen.

The input unit 120 comprises a keyboard, mouse, touch panel, and thelike. The input unit 120 accepts operations input by an administrator ofthe server device 100.

The storage unit 130 is configured with a storage device such as a harddisk. The storage unit 130 has recorded therein programs necessary forexecution of processing in the control unit 110, and data necessary forexecution of the programs. Specifically, it is desirable that thestorage unit 130 has an item information table 130A, a user informationtable 130B, and a mode information table 130C. FIG. 3 shows an iteminformation table 130A, and FIG. 4 shows a user information table 130B.For example, the item information table 130A stores, for each item, anitem identifier, an item name, parameters (attribute, hit points, attackpower, defense power, rarity, etc.), and an item added timing (the timewhen the item has become available in the game). The user informationtable 130B stores, for each user, user information including a user ID,a password, the user's game history (level, status, playing time,acquired items, mode information indicating a mode selection result),and probabilities that respective modes (described later) are selected(hereinafter, referred to as “mode selection probabilities”). Further,as shown in FIG. 5, the mode information table 130C stores modeidentifiers and mode names of a plurality of types of modes, and itemodds in the respective modes.

The communication unit 140 connects the server device 100 to the network300. For example, the communication unit 140 may include a LAN card,analog modem, or ISDN modem, and an interface for connecting it to theprocessing unit via a system bus or other transmission path.

Further, as shown in FIG. 2, the arithmetic processing unit 111 has, asfunctional units, an item lottery unit 111A, a mode selecting unit 111B,an odds control unit 111C, and an output unit 111D.

The item lottery unit 111A holds a lottery to determine an item to beprovided to a user from among a plurality of types of items. Thislottery is desirably displayed in such a manner that the odds of winningan item can be controlled in accordance with the parameters of the item.For example, the lottery may be displayed using a capsule toy or thelike in which a lever is rotated on the screen to eject an item, aroulette wheel, a lottery wheel or other lottery device, or a dartboard. The image used for a lottery is generated by the image processingunit 112.

The mode selecting unit 111B selects, from among the modes stored in themode information table 130C, a mode used for holding an item lottery.

Examples of the modes include a “non-duplicate mode”, “parameterguarantee mode”, and “variable odds mode”. The “non-duplicate mode”refers to the mode in which any item already owned by the user isexcluded from the lots so as to prevent the item from being won.

The “parameter guarantee mode” refers to the mode in which theprobability that the item won in a lottery has a prescribed attribute isguaranteed to be 100%. The probability being 100% will be hereinafterexpressed as being “guaranteed”. Examples of the parameter guaranteemodes include: a “fire attribute guarantee mode”, “water attributeguarantee mode”, and “thunder attribute guarantee mode” in each of whichit is guaranteed that an item having a certain attribute is won; and a“skill-attached item guarantee mode” in which it is guaranteed that anitem capable of exerting a specific ability, such as special attack orrecovery, is won.

The “variable odds mode” refers to the mode in which the odds of winninga specific item are increased compared to the odds in a normal mode.Examples of the variable odds modes include: a “newly added itemenriched mode” in which the odds of winning an item newly added to thegame are increased, and a “skill-attached item enriched mode” in whichthe odds of winning an item with a prescribed skill are increased.

The information stored in the mode information table 130C for therespective modes will now be described. As explained above, each recordin the mode information table 130C stores a mode identifier, a modename, and item odds for respective items in the mode. For example, inthe record for the “non-duplicate mode”, values indicating the odds ofwinning respective items when the user does not have the correspondingitems yet are stored as the item odds. These odds of winning items whenthe user does not have the corresponding items yet may be the samevalues as those in a normal mode.

In each of the records for the “parameter guarantee modes”, a prescribedvalue is stored as the item odds for any item having the parameter thewinning of which is guaranteed in that mode, and “0” is stored as theitem odds for the other items. For example, in the record for the “fireattribute guarantee mode”, a prescribed value is stored as the item oddsfor any item having the fire attribute, and “0” is stored as the itemodds for any item having an attribute other than the fire attribute.

Further, in each of the records for the “variable odds modes”, a valuehigher than that in the normal mode is stored as the item odds for anyitem having a specific parameter for each mode. For example, it may beconfigured such that, in the record for the “newly added item enrichedmode”, a value twice as large as that in the normal mode is stored asthe item odds for any item that has been newly added, and the samevalues as those in the normal mode are stored as the item odds for theother items.

One of these modes is desirably selected by a lottery. The mode lotterycan be held in various manners, as in the case of the item lottery. FIG.6 shows an exemplary mode lottery screen. In this example, a lot isdrawn for a mode in a roulette type lottery, from among “blank (normalmode)”, “fire attribute guarantee mode”, “water attribute guaranteemode”, and “thunder attribute guarantee mode”. It should be noted thatthe number of modes from which one mode is selected by a lottery, andthe types and combination of the modes are not limited to those shown inthis example.

It is also desirable that the mode selecting unit 111B controls the modeselection probabilities on the basis of the user information ofrespective users stored in the user information table 130B. For example,it may be configured such that, upon mode selection, the probabilitythat “blank (normal mode)” is selected is lowered as the user level ishigher. It may also be configured such that, in accordance with theprogress of the game, for example in a stage where a large number ofenemy characters having the fire attribute appear, the probability thatthe water attribute guarantee mode is selected is increased.Furthermore, the mode selection probability of a prescribed mode may bevaried in accordance with the items owned by a user. For example, in thecase where the user possesses a prescribed number or more of recoveryitems, the probability that the attack skill card enriched mode isselected may be increased. As such, the mode selecting unit 111Bdesirably controls the mode selection probabilities of the respectivemodes so as to compensate for the user's weak points. More specifically,it is desirable that the mode selecting unit 111B changes the modeselection probabilities for a user, which are stored in the userinformation table 130B, as appropriate, depending on the informationsuch as the user's playing time, level, and acquired items, and selectsa mode on the basis of the mode selection probabilities thus changed.

The odds control unit 111C refers to the mode information table 130C, onthe basis of the mode selected by the mode selecting unit 111B, tocontrol the item odds. More specifically, the odds control unit 111C maypass the item odds stored in the mode information table 130C, asarguments, to a subsequent processing stage. For example, in the modeinformation table 130C, for each of the above-described parameterguarantee modes, a prescribed value is stored as the item odds for anyitem having the parameter the winning of which is guaranteed in theselected mode, and “0” is stored as the item odds for any item nothaving the parameter the winning of which is guaranteed. The oddscontrol unit 111C may pass the stored item odds, as arguments, to theitem lottery unit 111A in the subsequent stage. Further, in thenon-duplicate mode, the odds control unit 111C checks the items acquiredby the user, which are recorded in the user information table 130B, sets“0” as the item odds for any item already owned by the user, and passesthe item odds (“0”), as an argument, to the item lottery unit 111A. Asfor any item not yet owned by the user, the odds control unit 111Cpasses the value of the item odds stored in the mode information table130C, as an argument, to the item lottery unit 111A. Further, in each ofthe variable odds modes, the odds control unit 111C desirably passes theitem odds stored in the mode information table 130C, as arguments, tothe item lottery unit 111A.

The output unit 111D outputs an image generated by the image processingunit 112. The output unit 111D may output image information to themobile terminal 200 to cause the image to be displayed on the screen ofthe mobile terminal 200. Alternatively, in the case where the serverdevice 100 is directly connected to a display, the output unit 110D maycause the image to be displayed on the display.

The process flow in the arithmetic processing unit when a user uses thegame system 10 to draw a lot for an item will now be described in detailwith reference to FIGS. 7 and 8. FIG. 7 is a chart illustrating theprocess flow in the server device 100, and FIG. 8 shows transitions ofscreens displayed on the mobile terminal 200 in the course of theprocess flow. It should be noted that the process steps included in theprocess flow described below may be performed in a different order or inparallel, or another step may be added between the process steps, aslong as no inconsistency arises in the processing content. Further, thestep described as one step for convenience sake may be performed in twoor more steps. The steps described as a plurality of steps forconvenience sake may be understood as one step.

First, the server device 100 accepts an access from a user using amobile terminal 200 (S101). At this time, a game start request istransmitted from the mobile terminal 200 to the arithmetic processingunit 111. It is desirable that the server device 100 requests an inputof login information such as a user ID and password before starting thegame. With this configuration, when the arithmetic processing unit 111in the server device 100 recognizes the login information, thearithmetic processing unit 111 can obtain the user's history informationlinked to the user ID, from the user information table 130B in thestorage unit 130, so that the game can be restarted from the lastinterruption.

When the server device 100 receives a game start request from a user,the image processing unit 112 generates an item lottery screen (screen500 in FIG. 8). The output unit 111D outputs this screen to the mobileterminal 200 of the user (S102). On the item lottery screen 500, asshown in FIG. 8, a lottery start button 500A for starting an itemlottery and a lottery image 500B displaying a roulette or other lotterydevice are displayed.

When the user selects the lottery start button 500A by clicking on ortouching the button on the item lottery screen 500, an item lottery isstarted. The result of the item lottery is displayed on an item lotteryresult display screen (screen 501 in FIG. 8) (S103). It is desirablethat, while the user is logged in, each time a lottery is held, thearithmetic processing unit 111 adds the item lottery result, as anacquired item, to the user information table 130B.

On the item lottery result display screen 501, as shown in FIG. 8, animage 501B of the item acquired by the user by the lottery and a “Next”button 501A for selecting a mode by a lottery are displayed. When theuser uses this screen to operate the mobile terminal 200 to select the“Next” button 501A, mode selection by a lottery is started (S104). Themode selection is performed on a mode lottery screen 502 in FIG. 8. Theresult of the mode selection is recorded, as a mode selection result(called “mode information”), in the user information table 130B by thearithmetic processing unit 111. The mode information is kept while themode is continued.

The result of the mode selection is displayed on a mode result displayscreen 503 in FIG. 8 (S105). On this screen, a mode lottery result image503B showing the selected mode, a “Next” button 503A for proceeding to anext item lottery, and a release button 503C for releasing the mode aredisplayed. When the user has selected the release button 503C, or whenthe result of the mode selection was “blank (normal mode)”, thearithmetic processing unit 111 determines that the mode has beenreleased (YES in S106), and the mode returns to the normal mode. At thistime, the mode information that has been kept in the user informationtable 130B is deleted (S107), and the screen returns to the item lotteryscreen 500.

On the other hand, when the mode selection result was not “blank” andthe user has selected the “Next” button 503A (NO in S106), an itemlottery screen 504 shown in FIG. 8 is displayed in accordance with theselected mode, while the state where the item odds are controlled byodds control processing (described later) is being maintained. On theitem lottery screen 504, a lottery start button 504A for instructing tohold a lottery in accordance with the selected mode, a lottery image504B displaying a roulette or other lottery device, and a release button504C for releasing the selected mode are displayed. When the userselects the lottery start button 504A, an item lottery corresponding tothe mode is held. The result of the lottery held in the state where themode is being maintained is displayed on an item lottery result screen505 in FIG. 8. When the user selects a “Next” button 505A displayed onthis screen, the item lottery screen 504 is displayed again, and alottery is held with the selected mode maintained.

On the other hand, when the user has selected the release button 504C onthe item lottery screen 504, the arithmetic processing unit 111determines that the mode has been released (YES in S106), and the modereturns to the normal mode. At this time, the mode information that hasbeen kept in the user information table 130B is deleted, and the screenreturns to the item lottery screen 500. Further, when the arithmeticprocessing unit 111 determines that the user has logged out (YES inS108), the arithmetic processing unit 111 deletes the information aboutthe acquired items (in other words, history information of the itemlottery results) recorded in the user information table 130B (S109), andterminates the process.

Odds control processing carried out when a lottery is held in the statewhere a specific mode has been selected will now be described withreference to FIGS. 9 and 10.

FIG. 9 is a flowchart illustrating the process flow in the“non-duplicate mode”. When the non-duplicate mode has been selected in alottery, the odds control unit 111C refers to the acquired items listedin the user information table 130B to check the items the user hasacquired during the logged-in period. The odds control unit 111C thensets the item odds for any item already owned by the user to “0” (S201),and passes the odds (“0”), as an argument, to the item lottery unit111A. As for the items not owned by the user, the odds control unit 111Cpasses the item odds stored in the mode information table 130C as theyare, as arguments, to the item lottery unit 111A. Next, the item lotteryunit 111A holds a lottery on the basis of the item odds received fromthe odds control unit 111C (S202). The arithmetic processing unit 111adds the item acquired by the user in the item lottery, as an acquireditem, to the user information table 130B as appropriate (S203). Theprocessing in S201 through S203 is repeated until the user releases themode. When the arithmetic processing unit 111 determines that the modehas been released (YES in S204), the arithmetic processing unit 111deletes the mode information recorded in the user information table 130B(S205), and terminates the non-duplicate mode.

FIG. 10 is a flowchart illustrating the process flow in the “parameterguarantee mode” and “variable odds mode”. First, the odds control unit111C refers to the user information table 130B to determine the selectedmode (S301). If the odds control unit 111C determines that the currentmode is the “parameter guarantee mode”, the odds control unit 111Crefers to the mode information table 130C and passes the item odds foreach item, as an argument, to the item lottery unit 111A (S302). In themode information table 130C, “0” is stored as the item odds for any itemthat does not have the parameter the winning of which is guaranteed, anda prescribed value is stored as the item odds for any item that has theparameter the winning of which is guaranteed. For example, in the casewhere the current mode is the water attribute guarantee mode, “0” ispassed to the item lottery unit 111A as the item odds for any itemhaving an attribute other than the water attribute.

If the odds control unit 111C determines that the selected mode is the“variable odds mode”, the odds control unit 111C increases the item oddsfor any item with a prescribed parameter, to a prescribed value (S303).For example, in the case where the selected mode is the “newly addeditem enriched mode”, the odds control unit 111C increases the item oddsfor any item that has been newly added to the game.

Each time the item lottery unit 111A holds a lottery on the basis of thereceived arguments (item odds) (S304), the arithmetic processing unit111 adds the lottery result to the user information table 130B (S305).The processing in S304 and S305 is repeated until the user releases themode. When the arithmetic processing unit 111 determines that the modehas been released (YES in S306), the odds control unit 111C resets anychanged item odds to a normal value. The arithmetic processing unit 111deletes the mode information recorded in the user information table 130B(S307), and terminates the mode.

Other Embodiments

While an embodiment of the invention has been described above, theinvention is not limited to the above embodiment; various modificationsand changes are possible on the basis of the technical ideas of theinvention.

For example, in the above embodiment, the mobile terminal 200 isconfigured to directly access the server device 100 via the network 300.Alternatively, for example in the case where the communication systemhas a Web server, it may be configured such that the Web server relaysthe communications between the server device 100 and the mobile terminal200. This can reduce the security risks.

Further, in the above embodiment, the mode selecting unit 111B isconfigured to determine a mode by a lottery. However, not limitedthereto, the mode may be determined in accordance with the progress ofthe game of a user, for example, or it may be configured to allow a userto select a mode arbitrarily. Although it has been described above thatthe mode selecting unit 111B selects a mode used for an item lotteryfrom among the modes stored in the storage unit 130, the modes do notnecessarily have to be stored. For example, branch conditions for theprocessing carried out by the odds control unit 111C for controlling theodds may be utilized.

DESCRIPTION OF REFERENCE NUMERALS

10: game system

100: server device

110: control unit

111: arithmetic processing unit

111A: item lottery unit

111B: mode selecting unit

111C: odds control unit

111D: output unit

112: image processing unit

113: memory

120: input unit

130: storage unit

130A: item information table

130B: user information table

130C: mode information table

140: communication unit

200A to 200D: mobile terminal

300: network

500 to 505: screen

500A to 505A: button

503C, 504C: button

500B to 505B: image

What is claimed is:
 1. A control method performed by a server devicewhich is connected via a communication line to a terminal deviceoperated by a user, the method comprising the steps of: selecting alottery mode from among a plurality of lottery modes; following theselection of the lottery mode, holding a drawing from among a pluralityof types of items on the basis of the selected lottery mode; andfollowing the holding of the drawing, providing the won item to theterminal device.
 2. The control method according to claim 1, wherein inthe lottery mode, the odds of winning a prescribed type of item amongthe plurality of types of items are increased.
 3. The control methodaccording to claim 1, further comprising the step of storing the itemacquired by the user, wherein in the lottery mode, the odds of winningan item that the user has not acquired yet among the plurality of typesof items are increased.
 4. The control method according to claim 1,wherein the step of selecting a lottery mode includes a step of holdinga lottery to select a lottery mode from among the plurality of lotterymodes.
 5. The control method according to claim 4, further comprisingthe step of storing user information associating the user with at leastone of level, game progress, acquired items, and playing time, whereinin the step of holding a lottery to select a lottery mode, the lotterymode selected in the lottery is varied in accordance with the userinformation.
 6. A server device connected via a communication line to aterminal device operated by a user, the server device comprising: alottery mode selecting unit which selects a lottery mode from among aplurality of lottery modes; a lottery unit which is operable, inresponse to the selection of the lottery mode, to hold a drawing fromamong a plurality of types of items on the basis of the selected lotterymode; and a providing unit which is operable, in response to the holdingof the drawing, to provide the won item to the terminal device.
 7. Aterminal device operated by a user and connectable to a server devicevia a communication line, the terminal device comprising a processorperforming the steps of: receiving, from the server device, a lotterymode selected from among a plurality of lottery modes; displaying thereceived lottery mode on a display; displaying a presentation of holdinga drawing from among a plurality of types of items on the basis of thereceived lottery mode; and displaying the item won in the drawing on thedisplay.
 8. A system including a terminal device operated by a user anda server device connected to the terminal device via a communicationline, the system comprising: a lottery mode selecting unit which selectsa lottery mode from among a plurality of lottery modes; a lottery unitwhich is operable, in response to the selection of the lottery mode, tohold a drawing from among a plurality of types of items on the basis ofthe selected lottery mode; and a providing unit which is operable, inresponse to the holding of the drawing, to provide the won item to theterminal device.
 9. A server device connected via a communication lineto a terminal device operated by a user, the server device comprising:means for selecting a lottery mode from among a plurality of lotterymodes; means operable, in response to the selection of the lottery mode,for holding a drawing from among a plurality of types of items on thebasis of the selected lottery mode; and means operable, in response tothe holding of the drawing, for providing the won item to the terminaldevice.
 10. A computer-readable storage medium having recorded therein aprocess for causing a computer to perform the steps of: gettingconnected via a communication line to a terminal device operated by auser; selecting a lottery mode from among a plurality of lottery modes;following the selection of the lottery mode, holding a drawing fromamong a plurality of types of items on the basis of the selected lotterymode; and following the holding of the drawing, providing the won itemto the terminal device.